[ 1218.744070][T11099] Could not find device with ifindex 2000 in netnsfd 11
[ 1218.744761][T11099] Could not find netns with fd: 2000
[ 1218.745325][T11099] Cannot link a netdevsim to itself
[ 1218.746006][T11099] Format for linking two devices is "netnsfd_a:ifidx_a netnsfd_b:ifidx_b" (int uint int uint).